DINA CAPPIELLO, Copyright 2006 Houston Chronicle |
June 13, 2006

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Concentrations of a dozen air pollutants in the Houston area pose significant risks to public health, and nowhere is the risk greater than in east Harris County, along the Ship Channel, a task force of public health and toxicological experts convened by Mayor Bill White concluded Monday.

In a city that ranks as one of the most polluted in the nation, the study provides, for the first time, a "to-do" list for reducing pollution, based on the risk to Houstonians' health, the mayor said.

Of the 12 compounds the scientists said posed a "definite risk,"seven are increasing people's chances of contracting cancer. Eight are linked to respiratory ailments. Several others tinker with the reproductive or immune system.

Yet, by no means is the risk even across the 10-county area evaluated. People living in east Harris County, beside industrial plants, the port and major highways, are exposed to twice as many of the most risky substances, the report found. And the scientists cautioned that the elderly, young and sick would be more susceptible to the pollution's effects.

"There is a myth that we need years and years more study before we take action against polluters ... we know enough now to know there is significant risk to our population," said Mayor Bill White, who convened the task force in March 2005, after reports by the Texas Commission on Environmental Quality and the Houston Chronicle exposed high levels of pollution in some city neighborhoods.

179 chemicals

The landmark 58-page report evaluates 179 chemicals that are released from car tailpipes, ships, industrial plants, and small sources such as dry cleaners and gasoline stations, for their potential to cause cancer, lung disease and other ailments.

The quality and quantity of information available on each chemical varied. In some cases, the scientists relied on computer projections of pollutant concentrations based on emissions in 1999. In others, they used data on 50 pollutants collected by 20 monitors in the Houston area in 2004. In the end, according to Dr. James T. Willerson, president of the University of Texas Health Science Center, which led a committee of eight scientists from five different institutions, the rankings came down to scientific judgment.

Environmentalists said Monday that although the report does not include any new scientific information, the hefty scientific credentials behind it, and the support of the mayor, are likely to bring renewed concern about the city's struggle with air pollution.

"It should make people stand up and take notice," said Jane Laping, executive director of Mothers for Clean Air. "Now, there is added weight."

The 12 riskiest compounds contain some usual suspects, such as ground-level ozone, the main ingredient in smog, and the fine particles in diesel exhaust and soot. But the bulk of the list comprises more obscure, toxic chemicals like ethylene dibromide, acrolein, and chromium VI, that are difficult to monitor and do not have federal health standards.

The mayor said the report would be used almost immediately to develop a regional plan that would focus on specific neighborhoods and sources. The first step is targeting the chemical benzene in the Clinton Park/Tri-Community and the Harrisburg/Manchester neighborhoods on the city's east side, the most polluted of the region's 895 census tracts. Though the bulk of the city was exposed to three or fewer of the 12 chemicals identified, the 28 tracts in east Harris County had three or more pollutants at concentrations posing a definitive health risk.

"There are some sad results of this study ... of the disproportionate impact of pollution," White said.

The mayor already has directed the city of Houston to use its monitoring equipment and target its enforcement in these communities. In the case of Harrisburg/Manchester, the city already has signed an agreement with Texas Petrochemicals, one of the biggest sources of 1,3-butadiene, a chemical use to make rubber, in the area to reduce its pollution.

But ultimately, the city is limited in what it can do, because the bulk of the pollution problem comes from outside its borders, and some of the main culprits are industrial plants regulated by federal environmental laws. The mayor said it would take the region, the state and local industry, to solve the problem.

'More work to do'

The East Harris County Manufacturers Association said that it would review the report.

Christine Miller, a spokesman for the group, which represents companies with facilities in east Harris County, said, "There's more work to do to further reduce emissions and to improve our understanding of human health effects and exposure."

The association, Miller said, will be participating in a two-year study examining chemical exposures in the area.

Mary Guerra, a resident of Manchester, is one of those who lives with an extra burden. The 610 bridge over the Ship Channel looms over the backyard of her tiny house.

"Sometimes I can't breathe," Guerra said. "I wish I could move out of here. I want to move out of here so bad."

The medical experts on the task force said people living in the most severely polluted communities should heed any air pollution warnings. When smog is bad, they said, the other chemicals tend to follow.